…well Steve, I was going with LM317 because that’s all I
know knew about. You have just expanded my horizons. I thank you for that.
I have made a lab power supply from an ATX power supply. It’s great! It looks like shit, but it’s great. Trouble is I thought I had plenty of banana jacks. I reality I had just two. So I went ahead and drilled the required holes and then went to buy more banana jacks - they had only small jacks. So I had to make the holes smaller using washers and a mig welder.
I did have a rocker that fit perfectly into the hole where the wires used to be, so that worked out pretty well.
12v ~ 7.5a, 5.5v ~ 14a, 3.3v ~ 19a. Perfect!
That looks good to me John. Sort of space-age.
As mentioned, the big limitation is that it only has a maximum of 12V, but if that’s all you’ll need, all is well.
My bench-top power supply, (which I rarely use because it takes up too much table space), was made using the switching power supply from a large, commercial printer that also had a computer motherboard. Luckily, though, it also had a 32V rail for the print-heads, so I used a separate internal regulator to get an adjustable supply from 1.25V to about 30V, along with the +5V, +12V and -12V rails. Not as high-powered as your’s, but I can draw 4A from the adjustable 1.25-30V rail, 1.5A from the -12V rail, 1A from the +12V rail and 8A from the 5V. It’s worked faithfully for over 20 years now. Like your’s there’s a fan in the original PSU - it blows out the back of my box and has an input vent on the side.
The printer was a good example of governments throwing money away. I bought it brand new as surplus. The government bought 2000 of these printers, to print postage stamps, receipts, scan documents and a few other functions. They were to be installed in post-offices.
They even had half a dozen large, high-quality Minebea bi-polar stepper motors in them.
No sooner did they get them made than they changed their mind and sold them off as surplus. I’m not sure just how much the government originally sold them for, but I got mine, (3 in total), for $41 each. The printers would have cost a couple of thousand dollars each to get made back then. I still have a number of the stepper motors here. They were the reason I bought the printers in the first place. The PSUs were a bonus, along with many other useful bits and pieces. (Photo-interruptors, microswitches and other sensors in particular.)
They were a fantastic score.